There is increasing interest and demand for adaptive music composition systems, which can change the character of generated music in real time, for use in diverse areas such as video game music generation, film score composition, and development of interactive composition tools. Previous music composition systems have tended to be monolithic and complex in their approach to automated music composition and have not been successful in mimicking human composed pieces of music. Furthermore, previous music composition systems have not been successful at adapting the music being generated to mood as it develops in a game or a film etc. Rather, the previous music composition systems rely on calling up different snippets of music that are classified under the given mood. This can be expensive for the makers of a video game as a composing and/or licensing fee must be paid for each snippet of music used. The complexity of the previous music composition systems have also made them difficult to use by a non-specialist.